The present invention first relates to a machine element that is designed for transferring a force and/or a torque and also for measuring the force to be transferred or the torque to be transferred. The invention also relates to an arrangement for measuring a force and/or a torque, wherein this arrangement comprises the machine element according to the invention. The invention further relates to a method for producing the machine element according to the invention.
U.S. Pat. No. 5,321,985 teaches a magnetostrictive torque sensor, in which a magnetostrictive layer is deposited on the outer surface of a shaft and is positioned opposite excitation and detection coils. The magnetostrictive layer can be charged by the excitation coils with a magnetic field, wherein the magnetic field emerging from the magnetostrictive layer can be measured with the detection coils. A torque acting on the shaft causes material stress in the magnetostrictive layer, whereby the relative magnetic permeability of the magnetostrictive layer changes as a function of the direction.
US 2007/0022809 A1 shows a device for measuring torques, in which a layer is formed from a magnetostrictive material in a shaft. This layer comprises an aluminum diffusion layer.
DE 39 40 220 A1 teaches a load sensor for measuring loads due to a torque acting on a shaft. Magnetostrictive elements are applied in two groups in a zig-zag pattern on the shaft. With the help of sensing coils, a magnetic flux is caused by the magnetostrictive elements.
From U.S. Pat. No. 5,052,232, a magnetoelastic transducer is known, in which a machine element is provided with two surrounding magnetostrictive coatings. The coatings have opposing, helix-like magnetizations.
From DE 698 38 904 T2, a torque sensor with circular magnetization is known. The magnetization is formed in a ferromagnetic, magnetostrictive material of a shaft and extends in a circle about the shaft.
U.S. Pat. No. 7,752,923 B2 shows a magnetostrictive torque sensor, in which a magnetically insulating layer and on this layer a magnetostrictive layer are deposited on a shaft. The magnetically insulating and electrically conductive layers are formed as a hollow cylinder and pressed onto the element exposed to torque.
EP 0 162 957 A1 teaches a method for measuring a mechanical stress on a shaft utilizing magnetostrictive properties of a magnetic material arranged on the shaft. Between the shaft and the magnetic material there is a non-magnetic carrier sleeve that is deposited on the shaft with a non-positive fit.
DE 602 00 499 T2 shows a position sensor with a magnetic structure made from two ferromagnetic collars.
DE 691 32 101 T2 shows a magnetic image sensor with a wire that has magnetization in the circumferential direction.
From DE 692 22 588 T2, a ring-shaped, magnetized torque sensor is known.
WO 2007/048143 A2 teaches a sensor with a magnetized shaft.
WO 01/27638 A1 shows an oscillation sensor with a shaft that is magnetized in the circumferential or longitudinal direction.
From WO 2006/053244 A2, a torque sensor is known that comprises magnetization on a rotating shaft. The magnetization has a circumferential construction.
U.S. Pat. No. 8,191,431 B2 shows a sensor arrangement with a magnetized shaft.
From DE 600 08 543 T2, a converter element is known that is provided for use in a torque or force sensor. The converter element is integrated into a shaft made from a magnetizable material and has magnetization oriented in an axial direction.
From JP 59-192930 A it is known to use a magnetic field sensor to determine the torque applied to a rotating shaft, wherein an anisotropic magnetic layer is deposited on the surface of the shaft. The layer is not permanently magnetized itself, but instead magnetized by a permanent magnet in one direction.